PREVIHMADA: A Cross-Sectional Study Protocol for Postpartum HIV Testing and Early Infant Diagnosis Among Women and Infants in Rural and Urban Madagascar

<title>Abstract</title> <p> <bold>Background</bold> : HIV prevalence in Madagascar has historically been low, but rising infections could lead to a generalized epidemic. Women of reproductive age and children are particularly vulnerable, with vertical transmission driving pediatric cases. Madagascar faces limited awareness, testing, antiretroviral therapy access, and early infant diagnosis (EID), which increases the risk of mother-to-child transmission (MTCT). The PREVIHMADA study aims to assess HIV prevalence among postpartum women and HIV status among HIV-exposed infants in both urban and rural settings, and to examine variations by geographical location and participant characteristics. The study also aims to strengthen dried blood spot (DBS)-based testing capacity, expand national EID using GeneXpert, and enhance community knowledge of HIV and MTCT. <bold>Methods</bold> : PREVIHMADA is a cross-sectional, multicenter study assessing HIV prevalence and potentially associated factors (demographic, geographical, socioeconomic, health-related and behavioral) among women and infants attending health facilities. Participants will be recruited from both urban and rural settings across healthcare centers of different levels in four regions in Madagascar: Boeny, Sofia, Diana in the north, and Analamanga in the central part of the country. In the study sites, we consecutively enroll all women attending the six-week immunization visit with their infants, granted informed consent. A questionnaire on maternal information is filled in by healthcare staff. Maternal HIV infection is assessed using a rapid diagnostic test, and infants born to HIV-positive mothers undergo early diagnosis through DBS sampling, tested and validated using GeneXpert and HIV DNA cell assays. <bold>Discussion</bold> : In a context of scarce data, the cross-sectional PREVIHMADA study offers a unique, infant-centered opportunity to assess HIV prevalence in mother–infant pairs. Its comprehensive, multi-method design engages both women and healthcare providers, capturing postpartum maternal HIV assessment and infant HIV exposure, with a focus on northern Madagascar, a region highly vulnerable to HIV transmission. EID is limited, especially in rural areas, contributing to rising pediatric HIV. The use of DBS and GeneXpert-based testing builds healthcare staff skills, strengthens national laboratory capacity, and introduces a scalable, resource-appropriate model for EID in the country improving early detection and timely treatment. Findings will generate critical evidence to inform Madagascar’s HIV strategy, enhance MTCT prevention programs, and support policies to reduce pediatric HIV transmission. </p>